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Author Topic:   Calibration Methods
Ken K.
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posted 10 May 2000 12:24 PM           Edit/Delete Message   Reply w/Quote
When our lab was first established in 1989, we wrote calibration methods for calipers, micrometers, etc. using the manufacturer's recommendations. We have been QS9000 certified since 1996 and auditors have never had a problem with this. That is until our last audit. He strongly suggested we use a federal or international calibration procedure for these instruments. I have looked high and low for these without any luck. What do you use for a calibration method for these? Shouldn't the manufacturer's recommendations suffice?
Also, since our calipers and mic's are critical we have them on a 30 day calibration schedule. Since some of the calibration dates fall on weekends and holidays, can we put a tolerance of say +\- 2 days without any repurcussions? Any help would be appreciated.

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Jerry Eldred
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posted 10 May 2000 03:02 PM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
My gut instinct is that the auditor doesn't have any business telling you a specific procedure to use.

What I believe is justified in is requiring you to have adequate procedures. If they meet requirements for a properly written, documented and revision controlled procedure, I don't quite comprehend how he can require you to use federal or equivalent procedures.

What I don't know is why he didn't like you procedures. Did the auditor, without any detailed review of the content of your procedures, make a blanket requirement that you use federal or international procedures? Or was the case that you only had the manufacturer's specs, and were using those as your calibration procedure?

An internally written procedure which includes a unique document number, revision control, environmental requirements, detailed requirements of exactly what standards must be used, step by step instructions for the calibration process, documented data points including upper and lower tolerance limits (there may be other details, but I believe I have covered the majority), and a review process by person(s) documented as competent to approve the procedure, should be indisputable.

If I had a procedure in that format (refer to NCSL - National Conference of Standards Laboratories Recommended Practice RP-3, "Calibration Procedures Content & Format for Measuring & Test Equipment (M&TE), Measurement Standards (MS), and Measurement/Test Systems (M/TS)"), and it gives detailed guidance on proper procedure writing.

As for federal or international procedures, one resource is GIDEP (Government - Industry Data Exchange Program). If you are a member, they have the various Air Force, Navy, Army and other procedures, most definitely including those for calipers and micrometers, etc. Perhaps ANSI or ASTM may have some documented procedures as well.

Those are just a few thoughts. Bottom line, you do need a good procedure. If in the auditors opinion it wasn't good enough, he may have made some recommendations. I have a problem with a registrar auditor being prescriptive. I've been to ISO9000 Lead Auditor course. I do remember the instructor (who was a 30 plus year veteran in the auditing business) saying that he gets irritated on a regular basis by auditors who try to tell auditees specifics as to how to resolve an issue. He stated that the auditor can write you a nonconformance for not having an adequate procedure (spec). But he can't tell you what to do about it, as it is considered to be a conflict of interest, as he is functioning as an auditor and a consultant (in his view, a no-no).

Perhaps some others could add to my thoughts. Hope I haven't confused the issue even further.

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Marc Smith
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posted 11 May 2000 05:42 AM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
I agree with Jerry and I thank him for a great, detailed response!

As far as the +/- 2 days on the recall - I would not have a problem with it but I might ask how you decided this would be sufficient. All you have to show / explain is that 2 days will not be a problem. I have had clients with a 2 week and 1 month 'extension' clause in their procedures for 6 month and 1 year intervals. Sometimes you just can't get to it.

That said, I don't recommend pushing the limit. Most of you calibrations should be on time. In your case, just wanting to avoid problems of a cal due date falling on a weekend, I cannot impagine a problem with a +/- 2 day 'tolerance' on a 30 day cycle.

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Ken K.
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posted 11 May 2000 07:18 AM           Edit/Delete Message   Reply w/Quote
I want to thank both of you for your response.
Our current calibration methods are very detailed and do contain what Jerry recommended. Every auditor before this one never had any problems with our internal methods. We did, in fact, file a complaint with Corporate concerning his remarks. This was our 8th audit, and we've never had the same auditor twice and I think that is part of the problem.
Also, we do have a clause in our calibration procedure that states if a calibration due date falls on a Saturday, it will be performed on the Friday before and if it falls on a Sunday it will be performed on the following Monday. If it is due on a holiday and no work is scheduled, then we either calibrate on the day before the holiday or the day after depending on our workload. I just wanted to clarify if this is permissable.
Again, I thank you for your response.

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barb butrym
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posted 11 May 2000 08:29 AM     Click Here to See the Profile for barb butrym   Click Here to Email barb butrym     Edit/Delete Message   Reply w/Quote
I wonder why you inflict such pain on yourself. The system does not allow for "s**t" to happen as it invariably does. But if that is what you want.......

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Ken K.
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posted 11 May 2000 09:14 AM           Edit/Delete Message   Reply w/Quote
Barb, I really don't understand your reply. Being a Lab Manager, QS9000 is very important to me and the "pain", as you call it, comes with the territory. After 7 audits we have had no noncomformaties in our lab and I'm proud of that. To me, all the effort was worth it.

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Ryan Wilde
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posted 19 May 2000 09:40 PM           Edit/Delete Message   Reply w/Quote
Are your calibrations solely used for internal calibrations or do you also do calibrations for external companies? The answer to that question will decide whether your auditor was right or wrong.

If you are doing only internal calibrations, the auditor MAY be off-base. What you have to establish is: Are they effective and appropriate for the use of the tools? If the calibrations are effective and appropriate, as I would surmise that they are due to the time span that they have been in use without a problem, then they are adequate for use by your lab. (By the way, tell your auditor the "effective and appropriate" part, they love those terms!)

On the other hand, if you do external calibrations, those for other companies, then it is strongly suggested that you use "well established" procedures, otherwise known as federal standards. I see that someone pointed you to GIDEP, which is what I use as procedures. I do modify them slightly, but all in all, the actual meat and potatoes of the procedure is unchanged. Customers expect to have a standard calibration technique employed.

I'll even be so nice as to give you a handy-dandy link to GIDEP. It is a great program, and the procedures are already written! There are a few catches though:
a) you have to be in the USA or Canada;
b) you have to be a defense contractor OR subcontractor of a defense contractor (this is easy, the DOD buys cars, and you are QS certified...);
c) you have to fill out a yearly useage report, which can be a pain.

If you decide to go through with it, the addy is http://www.gidep.corona.navy.mil/

It only takes a few days to get access, and they are wonderful people that are quite helpful. The database is available online.

Hope this helps you!

Ryan Wilde

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Ken K.
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posted 21 May 2000 08:36 PM           Edit/Delete Message   Reply w/Quote
Thank you for the reply Ryan. All calibrations we do are internal. I will be using your link on Monday to the GIDEP. I'm just curious at this point to see how our calibration methods compare to the federal standards.
Thank all of you for your replies.

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chen
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posted 01 June 2000 01:00 AM     Click Here to See the Profile for chen   Click Here to Email chen     Edit/Delete Message   Reply w/Quote
i think it is better to use national calibration procedures directly or convery it to your company procedures.

[This message has been edited by chen (edited 01 June 2000).]

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AJPaton
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posted 01 June 2000 09:53 AM     Click Here to See the Profile for AJPaton   Click Here to Email AJPaton     Edit/Delete Message   Reply w/Quote
Small question - +/- 2 days is a 4 day window in a 30 day calibration schedule. That mean you could have a 34 day lapse between calibrations. If your gauges are that critical, is a 13% deviation in calibration dates appropriate?

What general guidelines are out there on varying your calibration dates?

AJP

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Marc Smith
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posted 01 June 2000 10:11 AM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by chen:
i think it is better to use national calibration procedures directly or convery it to your company procedures.
I believe this is more a factor of the level of expertise in your company than anything else. If you don't have a qualified person to write your cal procedures, use a national standard if available. Typically a qualified technician is aware of existing national standards and knows whether to use them or to derive a procedure which fits the equipment. It should also be noted there are no national 'standards' for many types of equipment. Thus, this is not always an option.

My personal preference is Manufacturer's Recommended procedure be considered first.

[This message has been edited by Marc Smith (edited 01 June 2000).]

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Jerry Eldred
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posted 01 June 2000 10:20 AM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
I'll reply to a couple of points above.

1. The preference to use only national type procedures. There is certainly nothing wrong with that. It does make things simpler in an audit. But it is not necessary. If you are a US DOD contractor (or Canadian), it also saves expense. I have a preference to use GIDEP procedures, and utilize them where ever possible (and where it adds value or saves expense). But I would stand up to any auditor as for writing the procedure internally. The only holes I believe an auditor could poke in internally written procedures is as to the skill level of those writing them. I think as an auditee that you have a burden of proof to show evidence that the people writing your internal procedures have adequate skills and training to write them correctly.

2. Varying Calibration dates. It is not acceptable to go past the calibration due date in my opinion (I will explain below). The only exception should be over a weekend when there is no production in progress. If due date is on a Saturday, it can be calibrated Monday, only if the unit can't be used between Saturday and Monday. The object is not to use past the due date, not for the unit to be calibrated by its due date. You can calibrate 15 days after the due date, but you have to prove that it could not have been used between. An example may be a log in system where you document on what date the unit was received in lab for calibration.

As for variability of the due dates, the calibration interval is the amount of time within which you have some defined level of expectation (percentage probability) that a given unit will remain in tolerance. If it is a 30 day interval. The definition is that you have some defined level of confidence that the unit will remain in tolerance for that 30 day interval (either the manufacturers prescribed interval, or a statistically derived probability based on prior history for calibrations). To arbitrarily add a plus or minus amount of time you need to give evidence that the higher interval is still adequate. For example you began with a 30 day interval and allowed 34 days maximum, what evidence can you give the auditor that the unit has the same statistical probability of being in tolerance at 34 days. I would say you can't do that, because statistically, by definition, for each day you add to the interval, your statistical confidence that the unit will remain in tolerance will decrease.

Enuff' said.

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Ken K.
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posted 09 June 2000 01:54 PM           Edit/Delete Message   Reply w/Quote
Jerry, you brought up a point I might disagree with. I don't think this is the place to post this, but I'll take a chance.

You wrote;

"The only holes I believe an auditor could poke in internally written procedures is as to the skill level of those writing them. I think as an auditee that you have a burden of proof to show evidence that the people writing your internal procedures have adequate skills and training to write them
correctly".

Am I to beleive you feel an auditor can come into our(a)plant and question if the people doing certain jobs are qualified? Shouldn't the company, who put those people in their positions, determine if they are qualified or not? After all, if the company didn't think they were qualified, I don't think they would have hired or promoted them for those positions.

Sounds sort of scary to me.

Any thoughts on this?

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Jerry Eldred
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posted 09 June 2000 02:52 PM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
It seems that the debate here is 'common sense' versus 'what an auditor can manage to find wrong'.

Those two don't always seem to line up. The case in point is the discussion above wherein even though the company may well have had good procedures, the auditor seemed to find fault in the internally written procedures. In the common sense world, you hire good, qualified people to do their job (including write procedures). They write appropriate procedures, the procedures are approved within a good quality system, with good revision control, and properly adhered to. Trouble is, an external auditor can theoretically poke holes in that system. So one finds oneself creatinga system that is artificially 'better' to go above and beyond what works well for the company to the level of what additionally keeps the auditors happy.

I have been trained in a certified course as an ISO9000 lead auditor. But I have 23 years in metrology. And my experience has been that common sense (unfortunately) does not always rule. I am on your side, and theoretically don't at all disagree. The company should be able to make intelligent decisions as to what makes them able to produce consistent quality product. But my cynical side has also experienced the obverse - auditors that seem to come in and find holes in good systems (as well as miss holes in not so good systems).

My observations were aimed at attempting an answer as to where the auditor poked a hole in a good system, and how to satisfy the auditor.

My bottom line is, make and document a good system and follow it. Assure the system is adequate to assure the calibrations are performed correctly to subsequently assure product quality/integrity/reliability (which ever is applicable). When the auditors come (and they will in an ISO or QS type site), and poke holes in that good system, do within reason, what you have to to maintain that integrity, and correct the (albeit sometimes frivolous) audit discrepancy (non-conformance)).

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Marc Smith
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posted 10 June 2000 01:49 AM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
Jerry's response was - right on the mark. Thanks for the detail, Jerry. I'm pretty shoddy with answers. I would have just answered YES and Yes it is scarry....

quote:
Originally posted by Ken K.:
Am I to believe ... an auditor can come into our (a) plant and question if the people doing certain jobs are qualified?

Sounds sort of scary to me.


My thoughts are, YES - It's quite true! You have to be ready to stand your ground!

When I first put this web site up over 4 1/2 years ago, I had learned 1 thing about ISO which was worse with QS. See Elsmar.com/entry2.html#original - it says:

Do You... Understand the Intent?
Are You... Ready to (Can You) Explain?

The 'game' had begun in ernest. As I have said many times in these forums, I tell my clients to be ready from the beginning to fight.

Take a quick look at:
Elsmar.com/tis_me.html#lawyer

Again, this was written well over 4 years ago. The experience I was going through was the reason I put this site up back then! This thread, these forums, have evolved from those early pages and the trials at hand.

Some auditors are really good. Some are OK. Some are the devil incarnate. Things haven't changed all that much, either.

I still tell my clients at the first meeting:

You have to Understand every sentence of the document, the Intent of each sentence, and you have to be Ready to Explain how you meet the intent of each sentence! I can't explain for you... And - be ready to fight for your interpretation. You may have to.

As to the specifics of whether they can actually WRITE YOU UP for not having qualified people, you have to be ready to provide documented qualification requirements for the position (not to be confused with job criteria or job description elements) and be ready to discuss why those requirements are appropriate for the position - in case the auditor wants to push that far (which I have seen done many times, especially in QS audits).

Still scarry??

[This message has been edited by Marc Smith (edited 10 June 2000).]

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Marc Smith
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posted 10 June 2000 02:08 AM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Ken K.:
... brought up a point I might disagree with. I don't think this is the place to post this....
This is precisely the place to post what you posted!!!!! In many ways, it is the heart of this site!

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Ken K.
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posted 14 June 2000 09:34 PM           Edit/Delete Message   Reply w/Quote
I sure wish I would have found this sight years ago. Marc, you should be proud of what you put together. Finally, a helpful sight without all the BS.
Yes, still scarry. Another audit in September. What surprises await?!

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CarolX
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posted 28 June 2000 11:00 AM     Click Here to See the Profile for CarolX   Click Here to Email CarolX     Edit/Delete Message   Reply w/Quote
How can I access GIDEP? We are stricly a commerical house, and we do no business with the US or Canadian government. any suggestions?

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Jerry Eldred
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posted 28 June 2000 12:48 PM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
If you are a smaller company and "strictly a commercial house", it might be a little more difficult. I obtained my GIDEP membership not based on DOD contracts or actual contract numbers, but by being able to describe that our products are used somewhere by the military. The person processing my aplication had to get a supervisors approval, but I did receive a membership. I work for a major corporation that is readily perceivable by the GIDEP people to actually participate in work for the government. There is more than one way to do work for the government. There is the "MIL-STD" route, and there is the off-the-shelf" route. If you can determine if your company produces "off-the-shelf" products that are used by the government, that may be an avenue.

If you are able to get that info, just go to www.gidep.org. You should be able to extract information as to how to join from there. They are not highly restrictive on membership (in my experience), so it may be worth a try. It is possible though, that you may not be able to get a membership.

Worst case, if you can't get anything from GIDEP, send me an email, and I'll be glad to try to help out. My email is jerry.eldred@motorola.com .

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Ken K
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posted 28 June 2000 02:03 PM     Click Here to See the Profile for Ken K     Edit/Delete Message   Reply w/Quote
I sent in my participation request/user authorization on 6/26/00 and am waiting for a reply. I work for a large automotive interior supplier which I hope will get us approved. Does the offer apply to everyone Jerry? I might also need some help if I am denied.

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Jerry Eldred
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posted 28 June 2000 02:45 PM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
Feel free to email me. I am on the road the rest of this week, and it will be the end of next week before I will be able to reply. But again, just ask via email, as I don't want to get that detailed in the forum. Send to jerry.eldred@motorola.com

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Ken K
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posted 15 September 2000 10:26 AM     Click Here to See the Profile for Ken K     Edit/Delete Message   Reply w/Quote
After doing alot of searching, reading way too many calibration procedures, and attending a Mitutoyo calibration seminar, I still have a question about calibration procedures. Maybe it's not really a question, but a concern.

Let's say you have a micrometer (or any instrument) out on the production floor. This micrometer measures a critical dimension that has a direct bearing on parts going out the door. If this dimension is out of tolerance, the parts are either reworked or scrapped.

You get this micrometer in for calibration every 30 days. Whats the very first thing you do when doing a calibration on this instrument? What's your second step?

I'll post my concern after I read some of your replies. I asked this question at the seminar and was surprised at the responses I got. Feel free to respond.

(A special thanks to Jerry Eldred for the help you provided. Much appreciated.)

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Jerry Eldred
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posted 15 September 2000 10:49 AM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
Ken - You're quite welcome.

As to your question on your lates post. The first thing you should do with any instrument when it is received (after it has been allowed to acclimate in the lab environment as needed) is to take incoming readings. I am not a mechanical guru (mostly electronic, with some vacuum, pressure and flow, and semiconductor metrology). I have a feeling this may be a trick question. I think some people might say that the first thing you should do to a set of micrometers when you receive them is clean them. Again, I'm not a mechanical guru, so I don't know all the common industry practices. But I would stand by my position to take incoming readings before doing any kind of cleaning. If you clean first, and 'gunk' was the cause of incoming out-of-tolerance readings, you may miss out on finding out that product could have had erroneous readings.

I am a proponent of taking incoming readings before doing anything else to a measuring instrument for the above reasons.

The second thing to do would be the clean and inspect part. Then take more readings and make what ever adjustments may be needed, repeat those steps until the unit is in tolerance (as close to nominal as your internal methodology requires). Final readings then they are done.

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Ken K
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posted 15 September 2000 12:12 PM     Click Here to See the Profile for Ken K     Edit/Delete Message   Reply w/Quote
Jerry, not a trick question, but a real concern. At the seminar, out of 42 people, not one included this critical (at least I think it is) step. Most of them cleaned the instruments first without even inspecting
them. Without this first calibration, how would you know if the "out of tolerance" of the micrometer was due to your cleaning or if they came into the lab out of tolerance?
Every standard I found and read did not include this step and I was surprised.
I hope this small insight helps someone avoid a real problem down the line.

Verdict still out on the +/- 2 days for calibrations. We'll have an answer on 9/24/00. Our next audit date.

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Marc Smith
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posted 15 September 2000 01:29 PM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Ken K:

Most of them cleaned the instruments first without even inspecting
them.


Then they're doing it wrong IMHO. If they clean it first they have no idea if there was any debris which invalidated readings, among other things. Just my opinion -- and to be clear, I'm not a metrologist by trade.

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AJPaton
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posted 15 September 2000 01:55 PM     Click Here to See the Profile for AJPaton   Click Here to Email AJPaton     Edit/Delete Message   Reply w/Quote
My only dealings with calibration have been with an outside calibration house, so that might slant my view. Somehow, I doubt that they cleaned the equipment, since they charged extra for bringing it into calibration. Fixing it, even if it just meant cleaning the "gunk" out, was an extra charge. Don't have access to the calibration records anymore, but I think that I've seen "cleaned instrument" as a fix.

I guess that an internal calibration source would be more likely to clean before measuring.

AJP

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Jim Biz
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posted 15 September 2000 02:51 PM     Click Here to See the Profile for Jim Biz   Click Here to Email Jim Biz     Edit/Delete Message   Reply w/Quote
Don't want to put anyone on the wrong track (I'm no Met - guru either) But I would think one would state for internal calibration procedures at least that the first thing you do is verify current gage readings (check it out) then clean as needed for calibration/tests/R&R's etc. - if outside cal labs don't do it this way and you want it done - then it should be specified on the calibration PO.

(Ken - is there a logical path for tracing the manufacturers reccomended methods to a recognized standard ANSI etc. or at a minimum - calibrating with equip, that is traceable (certified gage blocks/masters?)

Best Regards
Jim

[This message has been edited by Jim Biz (edited 15 September 2000).]

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e.s.deo
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posted 17 September 2000 09:50 AM     Click Here to See the Profile for e.s.deo   Click Here to Email e.s.deo     Edit/Delete Message   Reply w/Quote
Dear Ken K & Jerry

As the requirements of the standard cl.4.10.6.4 goes, it is indicated that „preferablyšthe procedures to be based on the current issue of the natnl/intnl stds.
However the most important aspect is that the
procedures have to be appropriate to the job being performed.

As I look at it is suppose when a micrometer is being calibrated at an accuracy level
Of say .001 mm . Second case we take when it is required to be calibrated at an accuracy of say .01mm and third one say .1 mm (all this is for name sake!)

Now the standard may be appropriate for .01(say) however it may not be required to follow these stringent conditions for .1mm accuracy requirements. Also you may need a different standard or may require modifications for ensuring .001mm accuracy.
All the values are mere indications.

This means that just because you are follwing a national/international standard may not be sufficient for the job being performed.

As the second part of the querry goes
+/- 2days should not be a problem with 30 days as the frequency of calibration.
The evidence of appropriateness of this can be shown to the auditor may be by indications that the deviations in the accuracies in 30 days is not significant to reduce the calibration frequency and/or not to allow +2 days!

Thanks
E.S.Deo


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Ken K
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posted 20 September 2000 12:21 PM     Click Here to See the Profile for Ken K     Edit/Delete Message   Reply w/Quote
I originally started this topic because our calibration methods were questioned by our auditor. (As luck would have it, he is
returning for our next audit) After doing much research, I have come to the conclusion that the calibration methods we wrote and follow "in house" are more than adequate and I will let him know that if the subject comes up again.
I would suggest anyone writing calibration methods should use any of the manufacturer's or national standard's as a guide and
rewrite them to suit the needs of their company. One step should read; "All standards used in the calibration are traceable to
International Standards such as NIST".
We have always used the "before" and "after" cleaning steps in our calibration methods for calipers, micrometers, indicators, etc. It just made sense to calibrate before cleaning to eliminate what could turn into a major headache.
Also, the +/- 2 days issue is still a question mark. Our instructor at the seminar was a trained auditor and he did not hesitate to reply that + 2 days was not acceptable. His opinion was "zero tolerance" on the + side, but - would be ok but only as far as
weekends and holidays were concerned. I guess the old saying, "Ask 10 people a question..." applies so far.

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Jerry Eldred
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posted 20 September 2000 12:37 PM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
I'm sure I'll end being redundant on the below reply.

The +/-2 days for the calibration interval is one of those things that in practical terms probably would ALMOST never detrimentally impact product quality, but is very difficult to justify on paper. I think for example, if you had a pretty large sample size of all the same kind of micrometer, all the same model, all used identically -- if you evaluated them over a statistically significant length of time, you would end up with some sigma level confidence that they would pretty predictably be expected to remain statistically 'in-tolerance' for some pretty predictable length of time. Therefore if you extended the calibration interval even by two days (if you had an interval as short as 30 days, that is pretty significant), you have just statistically reduced your sigma confidence level of in-tolerance. And subsequently increased a probability of erroneously calling good product bad or bad product good. So from an auditor standpoint, if you have statistically established what your calibration interval ought to be, to then allow the extra two days, in the auditors mind is unnecessarily placing product quality at risk (which it truly is). The amount of increased risk varies by the partiuclars of the instrument and the lnegth of interval.

If it were my program, I probably quite honestly would not give that allowance. There are the small proportion of instruments wherein there may be added risk, and it is also difficult to justify in an audit. You can probably vrey slightly change the wording of your recall system such that perhaps your due date is two days less than the defined interval. Then the plus two days is built in to the established cal interval. That's just one idea. I'm sure there are plenty of other ways to conquer that type of issue.

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Ken K
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From:Wisconsin, USA
Registered: Jun 2000

posted 29 September 2000 01:58 PM     Click Here to See the Profile for Ken K     Edit/Delete Message   Reply w/Quote
Another day, another audit. Calibration methods were not even mentioned this time around. He didn't even glance at them. This time we spent 1.5hrs on lab temp and humidity. You had to be there to fully appreciate the experience.
We were given one non-conformance for something the auditor could not fully explain. So I'll try.
We have two tensile testers in the lab. We were originally two separate companies who were acquired by a large corporation during the merger years. These machines were specially ordered to run the materials each company produced. And they only run those materials.
The auditor asked if we have done Gage R&R on these machines. We told him we had and produced them for him. After looking them over, he said what he meant is if we have done the Gage R&R comparing the two to each other. We said we didn't because they were not similar. The load cells, clamps, etc. were suitable for the material each ran. He didn't see it that way. His reasoning was what happens if one machine goes down.
Does anyone have any idea's how we should proceed with the Gage R&R? Does anyone think it's not worth the effort?

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Jim Biz
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From:ILLINOIS
Registered: Mar 2000

posted 29 September 2000 04:00 PM     Click Here to See the Profile for Jim Biz   Click Here to Email Jim Biz     Edit/Delete Message   Reply w/Quote
I think I agree with you ... sounds like you have an auditor that is "not in tune with your practices" BUT? What do you do in each case if one of them "goes down?"

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Rick Goodson
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From:Wuakesha, Wisconsin, USA
Registered: Aug 2000

posted 29 September 2000 05:41 PM     Click Here to See the Profile for Rick Goodson   Click Here to Email Rick Goodson     Edit/Delete Message   Reply w/Quote
The fact that you have two instruments does not mean you have to use one as backup for the other or visa versa. It also does not mean you have to run a GR&R and compare them.
The comment on what do you do if one breaks is going beyond the scope of what the auditor should be looking at. What is his next question, what do you do if the building burns down? I would suggest this is a situation where you need to challenge.

Your PM program should minimize the probability of an equipment failure. If you do have an equipment breakdown, your options are numerous. Notifying the customers and stopping production until repairs are made is one option. I would suggest, because the equipment is specially modified, you should have a contingency plan for repair/replacement parts and maybe a spares program for high wear parts.

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e.s.deo
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Posts: 13
From:India
Registered: Aug 2000

posted 22 October 2000 05:59 AM     Click Here to See the Profile for e.s.deo   Click Here to Email e.s.deo     Edit/Delete Message   Reply w/Quote
Dear Ken K
It is appropriate for us to be concerned about the MSA studies which you feel as unnecessary in a particular scenario like this.
In this case as per the information provided here, the two equipments are not interchangeable.
In such a case the additional MSA considering their interchangeability does not arise.
If we consider the equipments as interchangeable, even then you only need to review the earlier TYPE MSA. The standard allows type wise MSA which may please be noted.

Thanks
E.S.Deo

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